DP-900 Describe considerations for working with non-relational data on Azure — 40 Questions

Question 1

A social media application stores user profile data as JSON documents. Each user's document has a different structure, with fields that vary based on user activity. The application needs to query these documents efficiently using SQL-like syntax and support high write throughput. Which Azure data store is most appropriate for this workload?

Accepted Answer

Azure Cosmos DB. Azure Cosmos DB is the most appropriate choice because it natively supports storing and querying JSON documents with varying schemas, offers SQL-like query syntax via its core (SQL) API, and provides guaranteed low-latency reads/writes at any scale with automatic indexing of all fields. Its multi-model nature and configurable consistency levels make it ideal for high-throughput workloads like a social media application.

Answer

Azure SQL Database

Answer

Azure Blob Storage

Answer

Azure Table Storage

Question 2

A ride-sharing application needs to store real-time GPS location updates from drivers and passengers. The data is ingested as key-value pairs where the key is the user ID and the value is a timestamped location. The application requires low-latency reads and writes for millions of concurrent users, and the data model is simple with no need for complex queries or joins. Which Azure NoSQL database API should be used for this workload?

Accepted Answer

Azure Cosmos DB Table API. Azure Cosmos DB Table API is the correct choice because it provides a key-value store with low-latency reads and writes, ideal for high-throughput scenarios like real-time GPS updates. It supports a simple schema-less data model where each item is a key-value pair, and it offers single-millisecond latency at the 99th percentile for both reads and writes, meeting the requirement for millions of concurrent users without complex queries or joins.

Answer

Azure Cosmos DB SQL (Core) API

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Azure Cosmos DB for MongoDB API

Answer

Azure Cosmos DB for Apache Gremlin API

Question 3

A global social media platform stores user profile images (JPEG) and activity logs in JSON format. The logs have varying structures based on the type of activity. The application requires low-latency reads of images from any region and the ability to query logs using SQL-like syntax. Which Azure data storage solution should they use for each data type?

Accepted Answer

Azure Blob Storage with a CDN for images and Azure Cosmos DB (SQL API) for logs. Azure Blob Storage is optimized for storing large binary objects like JPEG images, and integrating it with Azure CDN ensures low-latency reads globally by caching content at edge nodes. Azure Cosmos DB with the SQL API provides native support for querying JSON documents with varying schemas using SQL-like syntax, making it ideal for the activity logs.

Answer

Azure Table Storage for images and Azure Cosmos DB (Table API) for logs

Answer

Azure Files for images and Azure SQL Database for logs

Answer

Azure Disk Storage for images and Azure Cosmos DB (MongoDB API) for logs

Question 4

A retail company stores product catalog data as JSON documents. Each product has a different set of attributes depending on its category (e.g., electronics have 'voltage', clothing has 'size'). The application needs to query products by category and price range efficiently. Which Azure data store is most appropriate for this workload?

Accepted Answer

Azure Cosmos DB. Azure Cosmos DB is the most appropriate choice because it natively supports JSON documents with flexible schemas, enabling each product to have a different set of attributes per category. Its indexing policies can be configured to efficiently support queries filtering by category and price range, and it offers low-latency, high-throughput access ideal for retail catalog workloads.

Answer

Azure SQL Database

Answer

Azure Blob Storage

Answer

Azure Table Storage

Question 5

A media company stores large video files and associated metadata (title, duration, tags) as JSON documents. The application requires low-latency streaming of videos to users worldwide and the ability to quickly query metadata by tag. Which combination of Azure services should the company use?

Accepted Answer

Azure Blob Storage for videos and Azure Cosmos DB for metadata. Azure Blob Storage is optimized for storing large binary objects like video files, offering high-throughput streaming via HTTP/HTTPS and integration with CDN for low-latency global delivery. Azure Cosmos DB provides single-digit millisecond read and write latencies with automatic indexing, making it ideal for quickly querying JSON metadata by tag using SQL or MongoDB API. This combination separates storage concerns (blobs for raw video, document DB for structured metadata) to meet both streaming and query performance requirements.

Answer

Azure Blob Storage for both videos and metadata

Answer

Azure Cosmos DB for videos and Azure Table Storage for metadata

Answer

Azure Files for videos and Azure SQL Database for metadata

Question 6

A global gaming company develops a multiplayer game. Player profile data (username, email, preferences) is stored as simple key-value pairs and must be accessible with single-digit millisecond latency from any region. Game session logs are stored as JSON documents with varying fields (session ID, player actions, timestamps) and must be queryable by player ID and timestamp range using SQL-like syntax. The company wants to use a single Azure database service for both workloads. Which combination of Azure Cosmos DB APIs should they choose?

Accepted Answer

Table API for profiles and SQL API for logs. Option A is correct because the Table API provides a simple key-value store ideal for low-latency profile lookups, while the SQL API supports querying JSON documents with SQL-like syntax, enabling efficient queries on game session logs by player ID and timestamp range. This combination meets both workloads within a single Azure Cosmos DB account.

Answer

SQL API for both profiles and logs

Answer

MongoDB API for profiles and Cassandra API for logs

Answer

Table API for both profiles and logs

Question 7

A social media application stores user profiles as JSON documents. Each user profile can have different attributes (e.g., some have 'education', others have 'work experience'). The application needs to query profiles by any attribute with low latency. Which Azure data store is most appropriate?

Accepted Answer

Azure Cosmos DB (SQL API). Azure Cosmos DB with the SQL API is the correct choice because it natively supports schema-agnostic JSON documents, allowing each user profile to have varying attributes without requiring a fixed schema. Its indexing policies enable low-latency queries on any attribute, and it provides single-digit millisecond response times for point reads and queries, which is essential for a social media application.

Answer

Azure Blob Storage

Answer

Azure Table Storage

Answer

Azure SQL Database

Question 8

A healthcare application stores patient medical records as JSON documents. Each document contains a variable set of fields depending on the patient's conditions. The application needs to query records by any field and support high write throughput. Which Azure data store is most appropriate?

Accepted Answer

Azure Cosmos DB with SQL API. Azure Cosmos DB with SQL API is the most appropriate choice because it natively supports storing and querying JSON documents with variable schemas, enabling efficient queries on any field. Its multi-model architecture and configurable indexing policies allow high write throughput while maintaining low-latency queries, which is critical for healthcare applications with dynamic patient records.

Answer

Azure Blob Storage

Answer

Azure Synapse Analytics

Answer

Azure Table Storage

Question 9

A social networking application stores user profiles as JSON documents. Each profile can have different fields (e.g., education, work history, interests) depending on what the user fills in. The application also needs to traverse friend connections as a graph to recommend new friends. The development team wants to use a single Azure Cosmos DB account for both workloads. Which combination of Azure Cosmos DB APIs should they choose?

Accepted Answer

SQL API for profiles and Gremlin API for graph. The SQL API (formerly DocumentDB API) is optimized for storing and querying JSON documents with flexible schemas, making it ideal for user profiles with varying fields. The Gremlin API is designed specifically for graph traversal queries, which is required for recommending friends based on friend connections. Using both APIs on the same Cosmos DB account allows the application to handle both workloads efficiently within a single service.

Answer

MongoDB API for profiles and SQL API for graph

Answer

Gremlin API for both profiles and graph

Answer

Table API for profiles and Gremlin API for graph

Question 10

A manufacturing company collects sensor readings from thousands of IoT devices. Each reading consists of a device ID, a timestamp, and a numeric value. The data is stored as key-value pairs and must support low-latency reads and writes at a global scale. The company also needs to query the data by device ID and time range. Which Azure Cosmos DB API should they choose?

Accepted Answer

Table API. The Table API is the correct choice because it is designed for key-value workloads with a schema-less design, supporting low-latency reads and writes at global scale. It allows querying by partition key (device ID) and row key (timestamp) to efficiently retrieve data by device ID and time range, matching the IoT sensor data requirements.

Answer

Core (SQL) API

Answer

MongoDB API

Answer

Gremlin API

Question 11

A social media platform stores user profiles as JSON documents where each profile can have different attributes (e.g., education, work history, interests). The platform also needs to traverse friend connections to recommend new connections using graph queries. The development team wants to use a single Azure Cosmos DB account for both workloads while minimizing complexity. Which combination of Azure Cosmos DB APIs should they choose?

Accepted Answer

SQL API and Gremlin API. The correct choice is A because the SQL API provides native JSON document storage and querying for user profiles, while the Gremlin API supports graph traversal for friend connections. Using both APIs in a single Azure Cosmos DB account minimizes complexity by allowing each workload to use the most appropriate data model without managing separate databases.

Answer

MongoDB API and Table API

Answer

Cassandra API and SQL API

Answer

Gremlin API only

Question 12

A manufacturing company stores IoT sensor data as JSON documents in Azure Cosmos DB. Each document contains a device ID, a timestamp, and a varying set of sensor readings. The application frequently queries data by device ID and a time range to retrieve all readings for a specific device over a period. The development team wants to use an API that supports SQL-like queries on this JSON data. Which Azure Cosmos DB API should they choose?

Accepted Answer

Azure Cosmos DB Core (SQL) API. The Azure Cosmos DB Core (SQL) API is the correct choice because it natively supports querying JSON documents using SQL-like syntax, which aligns with the requirement to run SQL-like queries on JSON data. This API provides a rich query language for filtering by device ID and timestamp ranges, making it ideal for the described IoT scenario where documents have varying sensor readings.

Answer

Azure Cosmos DB MongoDB API

Answer

Azure Cosmos DB Cassandra API

Answer

Azure Cosmos DB Gremlin API

Question 13

A logistics company tracks shipments. For each shipment, metadata (ID, weight, destination) is stored in a relational table. The route history is a sequence of events (timestamp, location, status) that is frequently appended but never updated or deleted. The application needs to quickly retrieve the latest status of a shipment and occasionally run analytical queries over the full route history. The company wants to minimize storage cost and use Azure services. Which Azure data store should they choose for the route history?

Accepted Answer

Azure Blob Storage with append blobs. Azure Blob Storage with append blobs is the correct choice because route history is write-once, read-many (WORM) data that is frequently appended but never modified or deleted. Append blobs are optimized for sequential append operations, offering low-cost storage for large volumes of event data, and they support fast retrieval of the latest status by reading the last block. This minimizes storage cost while allowing occasional analytical queries over the full history via Azure Synapse or other analytics services.

Answer

Azure Cosmos DB Core (SQL) API

Answer

Azure Table Storage

Answer

Azure SQL Database with a JSON column

Question 14

A gaming company stores player profiles as JSON documents. Each profile can have different attributes; for example, some profiles include an 'achievements' field while others include a 'purchaseHistory' field. The application must retrieve profiles by player ID with single-digit-millisecond latency and also support SQL-like queries on any attribute. Which Azure data store should the company use?

Accepted Answer

B. Azure Cosmos DB Core (SQL) API. Azure Cosmos DB Core (SQL) API is the correct choice because it natively stores JSON documents with flexible schemas, supports indexing on any attribute for SQL-like queries, and guarantees single-digit-millisecond latency for point reads by player ID. This meets the requirement for both fast key-based lookups and ad-hoc querying across varying profile attributes.

Answer

A. Azure Table Storage

Answer

C. Azure Blob Storage

Answer

D. Azure Database for PostgreSQL

Question 15

A social media application stores user posts as JSON documents. Each post contains fields like post_id, author, content, and timestamp. The application needs to query posts by author and date range using SQL-like queries. Additionally, the application requires the ability to traverse follower relationships as a graph to suggest new friends. The development team wants to use a single Azure Cosmos DB account to minimize management overhead. Which combination of Azure Cosmos DB APIs should they choose?

Accepted Answer

Use the SQL API for the posts and the Gremlin API for the follower graph.. Option D is correct because Azure Cosmos DB supports multiple API models within a single account, but only one API per account. To handle both SQL-like queries on JSON documents and graph traversal queries, you need separate accounts: one using the SQL API (or MongoDB API) for the document workload and another using the Gremlin API for the graph workload. The question states 'a single Azure Cosmos DB account,' which is a constraint; however, the correct answer acknowledges that you cannot mix APIs in one account, so the only way to meet both requirements is to use two accounts—one for each API. The answer D correctly pairs the SQL API for posts and the Gremlin API for the follower graph, implying two accounts.

Answer

Use the SQL API only for both workloads.

Answer

Use the MongoDB API only for both workloads.

Answer

Use the Gremlin API only for both workloads.

Question 16

A social media application stores user sessions as JSON documents. Each session document has fields like sessionId, userId, startTime, endTime, and a list of pageviews. The application needs to quickly retrieve a session by its sessionId and also run queries like 'find all sessions for a user in the last 24 hours' using SQL-like syntax. The data has no fixed schema; different sessions may include additional optional fields like 'deviceType' or 'promotionCode'. Which Azure data store should the company use?

Accepted Answer

Azure Cosmos DB with SQL API. Azure Cosmos DB with SQL API is the correct choice because it natively supports storing JSON documents with flexible schemas, allows fast point reads by sessionId using a unique identifier, and enables SQL-like queries (e.g., filtering by userId and startTime) with automatic indexing. Its schema-agnostic design handles optional fields like deviceType or promotionCode without requiring schema changes, and it provides low-latency reads essential for real-time session retrieval.

Answer

Azure Table Storage

Answer

Azure SQL Database

Answer

Azure Blob Storage

Question 17

A social media company stores user-generated posts as JSON documents. Each post contains fields such as postId, userId, timestamp, and content. The application needs to query posts by userId and timestamp ranges with low latency, and also perform SQL-like queries across all posts. The data volume is growing rapidly and must scale globally. Which Azure data store should the company use?

Accepted Answer

B) Azure Cosmos DB SQL API. Azure Cosmos DB SQL API is the correct choice because it provides native support for querying JSON documents with low-latency, including indexed queries on fields like userId and timestamp. Its global distribution capability ensures data can be replicated across multiple Azure regions for low-latency access worldwide, while its SQL API allows SQL-like queries across all posts, meeting both requirements.

Answer

A) Azure Table Storage

Answer

C) Azure Blob Storage

Answer

D) Azure Cache for Redis

Question 18

A gaming company stores player session data as JSON documents. Each document contains fields like sessionId, userId, startTime, and a varying set of optional fields such as deviceType or campaignId. The application needs to query sessions by userId and startTime range using SQL-like queries, and also by sessionId with low latency. Which Azure Cosmos DB API should the company choose?

Accepted Answer

SQL (Core) API. The SQL (Core) API is the correct choice because it natively supports SQL-like queries over JSON documents, enabling efficient filtering by userId and startTime range. It also provides low-latency point reads by sessionId when a well-designed partition key (e.g., /userId) is used, and it offers automatic indexing of all JSON properties, including optional fields like deviceType or campaignId.

Answer

MongoDB API

Answer

Table API

Answer

Gremlin (Graph) API

Question 19

A healthcare organization stores medical imaging files (DICOM) that are actively used by radiologists for the first 30 days. After 30 days, the files are accessed infrequently for up to 5 years. After 5 years, they must be retained for legal compliance but are accessed very rarely. The organization wants to minimize storage costs. Which strategy should they use to manage the data lifecycle in Azure Blob Storage?

Accepted Answer

Store files in the Hot tier, move to Cool tier after 30 days, then to Archive tier after 5 years.. Option B is correct because it aligns the data lifecycle with the access patterns: Hot tier for frequent initial access, Cool tier for infrequent access after 30 days, and Archive tier for long-term compliance after 5 years. Azure Blob Storage lifecycle management policies can automate these transitions, minimizing costs by using the most cost-effective tier for each phase.

Answer

Store all files in the Hot tier and use lifecycle management to move to the Archive tier after 5 years.

Answer

Store all files in the Archive tier from the beginning to minimize cost.

Answer

Store all files in the Cool tier to balance cost and access.

Question 20

A global e-commerce company needs to store user session data (key-value pairs) for a web application hosted in multiple Azure regions. The data must support low-latency reads and writes (under 10 ms) and be automatically replicated across regions for high availability. The development team also requires the ability to query sessions by user ID using a simple key lookup and occasionally filter by secondary attributes such as timestamp. Which Azure data store should they choose?

Accepted Answer

Azure Cosmos DB. Azure Cosmos DB is correct because it provides globally distributed, multi-region writes with automatic replication, guaranteeing low-latency reads and writes under 10 ms at the 99th percentile. Its key-value API (Table API or SQL API) supports simple key lookups by user ID and secondary indexing on attributes like timestamp, meeting all stated requirements.

Answer

Azure Table Storage

Answer

Azure SQL Database

Answer

Azure Cache for Redis